With the increasing popularity of prepaid network services, such as prepaid mobile plans, in which a user of a mobile phone purchases a number of cell-phone minutes in advance, the network infrastructure required to support prepaid services must be enhanced to handle the increased traffic and processing requirements.
FIG. 1 is a block diagram illustrating a conventional system for telecommunications in which a large number of subscribers are prepaid subscribers. When a mobile subscriber makes a call, the call enters the core telecommunication network via a mobile switching center (MSC 100). If the mobile subscriber is a prepaid subscriber, MSC 100 must confirm that the subscriber's prepaid account has a sufficient balance before allowing the subscriber to access the network. To do this, MSC 100 typically queries a service control point (SCP) designated for handling prepaid queries and which may include the prepaid database itself. Such an SCP is herein referred to as a prepaid SCP, or PPSCP. In FIG. 1, MSC 100 sends a query to one of a bank of PPSCPs 102 through a signal transfer point (STP 104).
For example, MSC 100 may send an initial detection point (IDP) query to STP 104 (FIG. 1, message 1). STP 104 may forward the IDP query to the bank of PPSCPs 102 (FIG. 1, message 2), which may respond to the query with either a CONNECT message if the prepaid subscriber has a sufficient account balance or a CONTINUE message if the prepaid subscriber has an insufficient account balance (FIG. 1, message 3). STP 104 may then forward the response to MSC 100 (FIG. 1, message 4). MSC 100 may either allow or deny the prepaid subscriber access to the network, based on whether the response received from STP 104 was a CONNECT or CONTINUE message, respectively.
As the number of prepaid subscribers increases, the number of SCPs in the bank of PPSCPs 102 may increase, with a corresponding increase in the number of connections to the bank of PPSCPs 102. An increase in SCPs and connections required may drive up the costs of the system, not only in physical hardware but also in resources required to administer and maintain the additional nodes. In addition, the increase in traffic due to the increased number of queries to the prepaid database may cause overall network performance to suffer. For example, excessive network traffic caused by prepaid database queries may limit or impair the function of other nodes on the network, such as home location registers (HLRs), E.164 number mapping (ENUM) servers, home subscriber servers (HSSs), and the like.
Thus, there exists a need to minimize the number of PPSCPs required, and/or minimize the number of signaling links connecting the PPSCPs with the network or with each other. There also exists a need to reduce prepaid query traffic and the corresponding effect on network performance. Accordingly, there exists a need for methods, systems, and computer program products for performing prepaid account balance screening.